With 500 million people on Facebook, 150 million on Twitter and every Fortune 500 company represented on LinkedIn, many marketers are overwhelmed and overspent trying to engage their customers and prospects. The answer is to think small, going after nano-markets using hyper-local social media marketing tools. A nano-market is smaller than a niche, and it's a group of people with a very specific set of interests.

Previously, these people were hard to find, and communicating with them was costly. But hyper-local search and social media have made it easier to target nano-markets, and most of the tools required to be successful are free or nearly free.

You can't outspend the big brands, and you can't put more hours in than them, either. What you can do is play the game differently by focusing on nano-markets. There are many social media outlets that can help you do this. I'd like to discuss three of my favorites.

Twitter SearchTwitter Search is already the second most used search engine on the internet. More than 1 billion twitter updates are created and indexed monthly; this puts 150 million Twitter members at your fingertips.

Too many people miss the "Advanced" search button. And that's too bad because one of the most important features is the location-based search option. You can drill down and search for people only in your immediate area who are tweeting about topics related to your business or industry and engage them in real-time

One great example of this is Blenz Coffee in Vancouver, British Columbia. The company found people within 10 miles of each of their locations who were tweeting about coffee, lattes, Starbucks and other coffee-related terms, and then engaged them by inviting them to its locations. George Moen, CEO of Blenz, also created a short list of influential bloggers and Twitter personalities and booked one-on-one meetings with them.

According to Moen, the strategy has increased store traffic and sales of online gift cards significantly. The Blenz strategy also helped them achieve the status of one of the top Ambush Marketers during the 2010 Winter Olympics, according to The Global Language Monitor, an independent media monitoring organization.

Meetup
According to founder Scott Heiferman, the purpose of Meetup is to "use the internet to get off of the internet." With more than 18,000 organizers and a growth rate of 500,000 members a month, it has proven to be a powerful tool. For less than $100 per year, you can start your own Meetup on a specific topic. Members in your region who indicate an interest in this topic will receive notifications of your group and upcoming events. Additionally, you can search for people within other Meetups.

By holding Meetup events that build community, share best practices and improve people's lives, you can elevate your organization and be seen as a trustworthy community hub -- versus a vendor or salesperson. It will also give you real insight into how you can help your clients and prospects.

Contact complementary Meetup group organizers and hold quarterly joint events. This exposes each of you to the other's market. It also will accelerate the growth of both respective Meetups.

Another strategy is to target Meetups that interest your prospects. Many of these groups have forums and complete member profiles that allow you to connect with them through Facebook, Twitter or their personal blogs. Be sure to gain consent, and don't send unsolicited pitches to these people. Instead, look for opportunities to contribute to the success of their Meetup groups and communities. This contribution could be in the form of providing sponsorship, guest speaking or even finding a venue for the group.

FourSquare
Some might describe FourSquare as a social game. Users "check in" to a business with their mobile phone and whoever checks in the most times at a business will be named Mayor of that location. Often, users post this information on Twitter and Facebook. Many businesses offer incentives and rewards to frequent visitors, and with more than 3 million users globally, most major cities have several thousand users.

One savvy independent Apple retailer in California monitors who is checking into the other local computer stores and corporately owned Apple stores. He then follows them on Twitter and FourSquare. On Twitter he watches their conversations for opportunities to provide relevant advice. Many of these people have come to his store as a result of their online conversations.

Particularly for retail and service-based businesses, filling out a complete FourSquare profile is vital. You might also add FourSquare-only specials. People will see your special offers when they check in at your business or a nearby business.

Blenz Coffee encourages check-ins by giving a $5 gift card to a new Mayor at each location weekly. According to Blenz, this immediately increased and sustained the number of check-ins at its major locations.

These are only three of the guerrilla social media weapons available. While your larger competitors fill the marketplace with noise, you can connect purposefully with your nano-markets and win the marketing battle one customer at a time.

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Brittney's a Certified Financial Planner who can help you manage your business and personal finances and navigate the ups and downs of starting a business.